plural cruxes also cruces ˈkrü-ˌsēz How to pronounce crux (audio)
: a puzzling or difficult problem : an unsolved question
The origin of the word is a scholarly crux.
: an essential point requiring resolution or resolving an outcome
: a main or central feature (as of an argument)
… he discarded all but the essential cruxes of his argument.Carl Van Doren

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In Latin, crux referred literally to an instrument of torture, often a cross or stake, and figuratively to the torture and misery inflicted by means of such an instrument. Crux eventually developed the sense of "a puzzling or difficult problem"; that was the first meaning that was used when the word entered English in the early 18th century. Later, in the late 19th century, crux began to be used more specifically to refer to an essential point of a legal case that required resolution before the case as a whole could be resolved. Today, the verdict on crux is that it can be used to refer to any important part of a problem or argument, inside or outside of the courtroom.

Examples of crux in a Sentence

the crux of the problem is that the school's current budget is totally inadequate
Recent Examples on the Web The father-son duo were the emotional crux of many a Glee plotline, from Kurt’s bullying trauma to Burt’s cancer diagnosis. Shania Russell,, 19 May 2024 While viewers know the film’s crux is a damning interview, its plot provides a roadmap and the personal motivations that led each figure there. Armani Syed, TIME, 5 Apr. 2024 Narratively speaking, the story’s crux is an unlikely friendship. Longreads, 2 Feb. 2024 This impersonality is all the more dismaying because the dramatic crux of the film is exceptionally effective. Richard Brody, The New Yorker, 1 Feb. 2024 See all Example Sentences for crux 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'crux.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


Latin cruc-, crux cross, torture

First Known Use

1718, in the meaning defined at sense 1

Time Traveler
The first known use of crux was in 1718


Dictionary Entries Near crux

Cite this Entry

“Crux.” Dictionary, Merriam-Webster, Accessed 24 Jul. 2024.

Kids Definition

plural cruxes also cruces ˈkrü-ˌsēz How to pronounce crux (audio)
: the most important point
the crux of the problem

from Latin crux "cross, torture, trouble" — related to cross, crucial, crucify

More from Merriam-Webster on crux

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